Weed killing compositions



Patented May 11, 1937 I UNITED STATESV'PATE'NT OFFICE WEED KILLING COMPOSITIONS William Hunter Volck, Watsonville, Calif., as

Signor to California Spray-Chemical Corporaltion, Berkeley, Calif., a corporation of Delaware No Drawing. Application July 5, 1932,

' Serial "No. 620,984

7 Claims. (01. 167-45) The invention, in general, relates to sprays for which is injurious to animal or human life, nor the control of noxious plants, and more particuwhich presents a fire hazard. larly relates to petroleum base compositions and A further object of the invention is to provide to the method of preparation thereof for such use. a herbicide which will retain its effectiveness over While a large number of the compositions in a relatively long period of time, for a given quan present use for destroying weeds are generally tity applied. efiective in that respect, many of the compounds Other objects of the invention, together with possess inherent qualities which render their use some of the advantageous features thereof, will dangerous. For example, weed killing compounds app ar from th f llowi g d s r pt n of t 11) such as arsenical dust and sodium arsenate have ferred embodiment of the invention and the prebeen effectively used but cannot be employed with ferred process of Preparation thereofsafety in vicinities where cattle feed, because The d killer of y invention is preferably of the danger of poisoning the stock. Other commade from a petro eu base and, in its preferred monly employed compositions such as sodium r form, comprises a composition, either emulsified calcium chlorate have given satisfactory results 0 u e fi consisting of natural petroleums.

' in so far as control isconcerned, but the treated a ti s r p du t t r a ts areas present fire hazards, inasmuch as these taming a a d a aromatic constitucompositions oxidize readily and combustion is vhhts' fl together W t ulphur p e er b y o likely to occur if glass is lying about in the treated the Point Of Saturationareas; as is often the case. In the next preceding paragraph, I have re- 20 Natural petroleums or fractions thereof also ferred to t ts of petroleum or petroleum have been used more or less extensively for e tillates containing unsaturated constituents of killing, inasmuch as ithas been discovered that such s as x plif i n of t typ s f bases these oils contain certain amounts of herbicidal for y composition The extracts 130 which I ingredients. Further, a liquor containing these refer a d which a f a s f th preferred 25 herbicidal impurities of oil, in concentration, embodiment of y invention e t e e has been somewhat eiicctivel employed, the tracts commercially k w as s1u e ,h, nliquor being an extract of petroleum distillates before n d, ut at a xt ts containing the unsaturated constituents thereof tained by treating petroleum distillates with liqand obtained by treating the distillates with suluefied Sulphur dioxidea t of t Characphuric acid. This extract is commercially known ter a h p ss f u a tur h r f r a s1udge" described in United States Letters Patent No.

I have discovered that certain fractions, such 9.11553, issued on February 1909 Lazar as gasoline and kerosene, are less herbicidal than "Edeleanu and are commercially known as stove distillates, and that the latter, in turn, are anu extractsless herbicidal than lubricating oils and that this The addition of sulphur to y 1 at s, to less herbicidal property of the lighter fractions is, natural petroleums, fractions thereof, or to the in the main, d t th greater rapidity with aforementioned extracts, materially increases which the herbicidal ingredients of such lighter the efiectlveness there a a Weed kllleri 40 oils are evaporated and removed from the plant. have found that the mre $}11phur dlssolved Th use of t natural petroleum, fractions the oil, the greater the toxicity of the composithereof, or of sludge is attendant with several tion' Accordingly any of the Oils in accordance disadvantages and unsatisfactory results. In 33 ga gg fig zg g gg igg gzig general, an unsightly residue is left in the treated temperaiureg a certain amount 6 sulphur 5 areas a in H.164 case of the presence of will dissolve in the oils and the quantity of sulfree acid therein eats the equipment necessary which can be introduced varies, of course for applying the same- Further the sludge is in accordance with the basic oil used. For exof such viscosity as to be unmanageable, and ample, I have found t t, a sulphur dioxide often plugs the equipmentkerosene extract dissolves in the neighborhood It is an object of my invention to provide a of 7.7 grams of sulphur to approximately 500 cc. commercial herbicide which is relat v y mple of the extract, which is 58 grams to the gallon and inexpensive to prepare, which is readily apor, in the order of approximately one tenth of a pli to the plants, a which, upon pp pound of sulphur per gallon oi the extract. In-

does not leave an unsightly residue nor a residue creased quantities of sulphur, perhaps in the oil is exceedingly effective in the destruction of Weeds, in order to provide a herbicide which does not leave an unsightly residue in the treated area and a herbicide which can be readily sprayed with a conventional spray device, I prererably employ, as a base for the composition, the lighter fractions. I have also used successfully a sulphur saturated mixture of sulphur dioxide extract, in the amount of approximately 25% by weight, and Diesel oil 2'7 plus, in the amount of approximately by weight. Although, as hereinbefore stated, these lighter fractions alone have less phytocidal properties than the heavier fractions due to the greater rapidity with which the herbicidal components of such lighter oils are evaporated and removed from the plant, I have found that these lighter oils, when saturated with sulphur, are of such viscosity as to permit of the formation of films and of the retention thereof for appreciable periods of time upon the plant surfaces, thereby resulting in effective control of the weeds before evaporation of the oils.

In order to use the product of my invention economically as a spray, I may form an emulsion thereof by dissolving an agent in the mixture of oil and sulphur which will permit a uniform mixture of the product and water to take place, and which stabilizes the emulsion. Preferably, a miscible oil is first formed by dissolving in the sulphur saturated oil a soap containing pine oil, although creosote soaps can be used if desired. The miscible oil is then mixed with water, a satisfactory mixture being one part of the solution to approximately eight parts of water, although the amount of water mixed with the solution is not critical.

Instead of incorporating a prepared soap into the weed killer oil mixture, I may add thereto a fatty acid, such as oleic acid, or a mixture of oleic acid and resin, in such proportions that mixtures of the weed killer oil and water will emulsify upon the addition of an alkaline substance, such as caustic soda, caustic potash, sodium carbonate, ammonia, sodium polysulphidc, ammonium polysulphide, or a mixture of ammonia and sulphite waste liquor. The character of the emulsion so formed is determined by the percentage of fatty acids in the oil and the alkaline substance added to form normal emulsions in which the oil particles are surrounded by and dispersed in Water. The preferable percentage of fatty acid to oil may vary from one to five per cent, and the alkali is preferably sodium hydrate or ammonia. The quantity of alkali preferably is sufilcient to saponify the fatty acid and not greatly in excess of this amount.

While I have described the preferred embodiment of my composition and process of preparation thereof, it is to be understood that the appended claims are to be accorded a range of equivalents commensurate with the state of the prior art.

I claim:

1. A weed killing composition comprising uncombined sulphur dissolved in a petroleum oil base containing unsaturated constituents, the sulphur being in amount sufficient to makea substantially saturated solution.

2. A weed killing composition comprising uncombined sulphur dissolved in an extract of a distillate of petroleum which distillate has a su agent mount of unsaturated constituents thereiri to render it herbicidal to an appreciable extent, the sulphur being in amount sufficient to make a substantially saturated solution.

3. A weed killing composition comprising uncombined sulphur dissolved in a petroleum oil substantially completely soluble in liquid sulphur dioxide, the sulphur being in an amount suificient to make a substantially saturated solution.

4. A weed killing composition comprising uncombined sulphur dissolved substantially to the point of saturation in a mixture of approximately 75% by weight of Diesel oil 27 plus and 25% of liquid sulphur dioxide extract of petroleum oil.

5. A weed killing composition comprising uncombined sulphur dissolved in a petroleum oil base, which oil contains a sufficient amount of unsaturated hydrocarbons to render it herbi-,

cidal to an appreciable extent but which is sufliciently volatile not to leave a residue injurious to animal life after application, the sulphur being in amount suflicient to make a substantially saturated solution.

6. A weed killing composition comprising uncombined sulphur dissolved in a petroleum oil of kerosene boiling point range substantially completely soluble in liquid sulphur dioxide, the sulphur being in an amount suilicient to make a substantially saturated solution.

7. A weed killing composition comprising uncombined sulphur dissolved substantially to the point of saturation in a liquid sulphur dioxide extract of a petroleum oil.

WILLIAM HUNTER VOLCK. 

